Double-walled box



G. E. STRUBLE DOUBLE-WALLED BOX Dec. 30, 1958 4 Sheets-Sheet 1 Filed Aug. 23, 1955 INVENTOR.

GLENN E. STRUBLE lllllllL MAM M4 77 ATTORNEYS Dec. 30, 1958 G. E. STRUBLE 2,866,587

- DOUBLE-WALLED BOX Filed Aug. 25, 1955 4 Sheets-Sheet 2 IN VEN TOR.

GLE NN E STRUBLE ATTORNEYS Dec. 30, 1958 G. E. STRUBLE DOUBLE-WALLED BOX 4 Sheets-Sheet 3 Filed Aug. 25, 1955 INVENTOR.

GLENN E.STRUBLE ATTORNEYS Dec. 30, 1958 G. E. STRUBLE DOUBLE-WALLED BOX 4 Sheets-Sheet 4 Filed Aug. 23, 1955 FIG-15 fl II III!!! pill lllll I INVENTOR.

GLENN E. STRUBLE ATTORNEYS 2,865,587 DOUBLE-WALLED BOX Glenn E. Struble, Hamilton, Ohio, assignor, by mesne assignments, to Diamond Gardner Corporation, a cor poration of Delaware Application August 23, 1955, Serial No. 529,992

4 Claims. (Cl. 229-34) This invention relates to double-walled boxes of the type having hollow walls, and particularly to construetions for forming corners on such boxes and locking the boxes in erected position.

A primary object of the invention is to provide a double-walled box of improved design, including corner constructions which lock the box in erected position.

A further object of the invention is to provide such a double-wall box using a unitary blank of sheet material, with a minimum of waste material in the cutting and scoring of the blank.

Another object of this invention is to provide a double-walled box wherein locking tabs extend from the top and bottom panels of the side walls into the hollow end Walls, providing for proper spacing of the end wall panels and for locking the corners of the box to hold it in erected position.

Other objects and advantages of the present inventio will be apparent from the following description, the accompanying drawings and the appended claims.

In the drawings- Fig. 1 is a plan view of the unitary blank of sheet material from which the box is formed;

Figs. 2 and 3 are detail views of one corner of the blank, showing the formation of the blank into knocked down or fiat folded form;

Fig. 4 is a detail view of one corner of the box after it has been erected from the position of Fig. 3;

Fig. 5 is a perspective view of one corner of the box in the same position as in Fig.4;

Fig. 6 is a perspective view of an intermediate step in the direction of the box;

Fig. 7 is a perspective view showing a completed corner of the erected box;

Fig. 8 shows the erected box with one end wall completely folded and the other end wall prepared for erecting and locking beneath the tabs on the side walls;

Fig. 9 is plan view of a blank for forming another double-walled box in accordance with the invention;

Figs. 10 and 11 are detail views of one corner of the blank of Fig. 9 showing the progressive steps in folding the box into knocked-down form;

Fig. 12 is a view similar to Fig. 11 showing the side wall erected; a

Fig. 13 is a perspective view of one corner of the box with the side wall erected as in Fig. 12;

V Fig. 14 shows an intermediate step in the erection of the end wall;

Fig. 15 is a perspective view of the completed corner construction of the box; and V Fig. 16 is a perspective view of the box of Fig. 9 with one end wall erected and the other end wall in unfolded condition.

Referring to the drawings, which illustrates preferred embodiments of the present invention, and particularly to Fig. 1; the blank there illustrated includes a bottom it? connected through opposite parallel score lines 11 2,356,58? Patented Dec. 30, 1958 ice to a series of panels for providing hollow side walls at opposite sides of the box. Each of these side walls includes an outer side wall panel 12, a top side wall panel 13, an inner side wall panel 14 and a bottom side wall panel 15. The panels 12, 13, 14 and 15 are separated from each other by score lines extending parallel to score line 11 and providing for folding of the end wall panels over and over toward the center of bottom 10 into knocked-down form, and eventually into erected condition.

At opposite ends of the bottom, hinged thereto along a score line 16, are hollow end Walls each comprising an outer end wall panel 17, a top end wall panel 18 and inner end wall panel 19, and a bottom end wall panel or tucking flap 20. At each corner of the box, integrally hinged to the ends of outer side wall panels 12 along score lines 21, are locking flaps 22 which are separated from the outer end wall panel 17 by a slit 23. The inner side panels 14 are shortened in length at each end with respect to the outer side panels 12 by a distance equal to the thickness of the end walls, which is equivalent to the width of top end wall panels 18. The inner side panels 14 are separated from the top and bottom side panels 13 and 15 by a slit 25 extending transversely of the ends of the side panels 14, and slits 26 extend from the centers of slits 25 to the edge of the blank, thereby providing extensions on the top and bottom side wall panels which form upper locking tabs 28 and lower locking tabs 30 at each corner of the box. These locking tabs are integral and coplanar with their respective top and bottom side wall panels, and accordingly will extend into the end walls of the box upon erection thereof, as will presently be described.

Suitable adhesive is applied, as by glue wheels 32 (Fig. 1), to the edges of the blank, along panels 15 and the adjacent portions of tabs 30. Panels 14 and 15 are then folded inwardly along the score lines between panels 13 and 14, to the position shown in Fig. 2, and then the side wall panels are folded inwardly along score line 11, to the position in Fig. 3. The shaded portion 33 on bottom 10 in Fig. 2 indicates the area of the bottom to which the panel 15 will adhere,

and in Fig. 3 the side wall is shown with the panels 15 and 14 hidden, and with the remainder of the side wall panels, folded flat along the sides of the box blank. In this condition the box is in knock-down or flat folded condition, suitable for shipping, storage, or the like.

The first step in erection of the box is illustrated in Figs. 4 and 5, showing the folding of the side wall panels into an upright position to provide a hollow side wall. In this position the locking tabs 28 and 30 extend inwardly from the side wall along the end of the box. The locking flap 22 is then folded inwardly, as indicated by the arrow 35, to a position wherein it extends vertically between the tabs 28 and 30 and across the open end of the hollow end wall at the corner of the box. The end wall panels are then folded upwardly, and inwardly as in Fig. 6, into surrounding relation with respect to the flaps 22 and the tabs 28, and the bottom end wall panel 20 is tucked beneath the lower tabs 30, so as to be sandwiched between these tabs 30 and the bottom 10 as seen in Fig. 7. Thus, the box is held in erected condition, with the flaps 22 prevent: ing collapse of the side walls due to their wedged condition within the end walls, and with the hollow end walls locked in erected condition by tucking of the end wall panels 20 beneath tabs 30, and with their collapse prevented by the upper tabs 28.

Referring to Fig. 9, another double-walled box provided by this invention is illustrated in blank form, and

, includes a bottom 40 having integral. extensions at its opposite sides separated therefrom by fold lines 41.

Each of these extensions is subdivided by-a seriesof and bottom panels 45. The other sides of bottom 40 have integral extensions connected. to the bottom by fold. lines,46,- and each of these extensions is sub-divided by a. plurality of parallel fold lines to providea series of panels for forming hollow end walls on the box. Each of theseend walls includes an outer panel 47, a top panel 48; an inner panel 49. and a bottom or tucking panel 50.

As willbe apparent from an inspection of Fig. 9, the inner side wall panels 44, and the adjacent bottom side wall panels 45, are shorter in length than the remainingside wall panels .by, a distance at each end equal to the thickness of the erected end walls, thatis, a distance equal to the. width of the end-wall. top-and bottom panels 48, and 50. Thus,. thetinner andbottom side. wallfpanels are separated from the, top side wall panels43by slits or cuts 52, and the material at theadjacent ends of thepanels. 44 remains integral with the upper or top side wall panels43 and extends coplanar. therewith, as will presently be described. This providesan upper locking tab 55 at each cornerof the box, and integrally hinged tothe tabs 55 are extension strips 56 which are in turn connected along scorelines 57 to outwardly extending, portions of the blank adaptedto provide lower locking;

tabs 58 at each corner of the box. In addition,. a lock.- ing flap 60.is hinged alonga foldline 61 to thecommon edge of the upper side wall panels 43 and the upper locking tabs 55.

Referring to Fig, 10, one: corner of the blank shown in Fig. 9 is illustrated with the bottom side wall panels 44 and 45 and the tabsSBand extensions 56 folded back upontheinner side wall, panelt44, by folding along the scoreline between'panels. 43: and 44. Suitableadhesive is then applied to thebottom surfaceof panel: 45

and to the adjacent aligned surface. of the lower tab 58 We suitable glue wheeli65. The glued. portions are then adhered to the shaded area 66 on bottomt40tby foldingtheside walls over alongt score line 41, as shown in. F1g,.11.. The blank isthen assembled; in knocked-down or flat folded form for shipping or storage purposes.

The erection of this box proceedsi'n the same manner as, previously described in connection with the box in Figs.3-8. Thus, in Fig. 12 the side walls have been folded into an erected.- form withv the panels 42 and. 44 extending vertically withrespect to the-bottom 40; This same condition of the box isshown in perspective in boxand. across the end thereof. The bottom end wall ortucking flap 50 is then sandwiched between the lower locking tab 58 and bottom 40 and the end walls of the boxthus locked inplace. Fig. 16 illustratesthegeneral appearance of the box with one end wall completely erected, and the other end wall infiat form preparatory toenfolding about the locking tab and flaps;

Thus, it'will be seen that the presentinvention-provides double-walled box constructions which are simple and economicalto manufacture and easy to assemble. The locking tabs and flaps provided in each of the above described corner constructions positively prevent the unfolding 'of the hollow sidewalls and-furthermore pro vide a relatively strong and tight assembly at thecorners ofthe bxes. Inaddition, the corner locking construction of this invention is especially adaptable to doublewalled .boxes; wherein the side. and end walls are of and 58, the I V which extend substantially. at right angles from the side wall of the different thicknesses. Thus, for example, in the box of Figs. 1-8 the top-andbottomendwall panels may be either wider or narrower than the top and bottom s de wall panels, with the widthof the locking tabs being variable to conform to the thickness of the end walls.

While the forms of articles herein described constitute preferred embodiments of. the invention, it is to be understood that the invention is not limited to these preclse forms of articles, and that changes made therein without departing from the scope of the invention which is de fined in the appended claims.

What is claimed is:

1. In a double-walled box of the character described, a unitary blank of sheet material scored and folded to provide a bottom, tubular side walls extending from opposite sides of said bottom, locking tabs projecting from the top and bottom of said side walls along the ends of said box at eachcorner of said box, an integral strip connecting the ends of said tabs at each corner of said box, locking flaps integral with said side walls and extending between said tabs at the corners of said box, tubular end walls folded about said tabs and said flaps, and a tucking panel on each said. end wall tucked beneath the bottom said tabs to retain the box in erected condition.

2. A double-Walled box. formed from a unitary blank of sheet material comprising, a bottom, end walls including inner, outer, top and-bottom panels, side Walls including inner, outer, top and bottom panels, upper lockingtabs projecting from said top side wall panels across the ends ofsaid box, lower locking tabs adhered at one end to said bottom. in the corners of said box, the remainder of said lower, locking tabs being free from and resting upon said bottom, integral strips connecting said upper and. lower tabs, locking flaps hinged from the ends'of said top end wall panels and the adjacent edge of said upper tabs, s'aid flaps being foldable into a position extending vertically between said tabs at the corners of said. box, and said. end walls being foldable in enveloping relation about said upper and lower tabs and said flap with said bottom eudwall panel tucked between the free portion of said lower tabs and said bottom to retain the box in erected condition.

. 3. A unitary blank for forming a double wall box comprising a sheet of material having score lines therein defining a generally. rectangular bottom, a plurality of score lines extending parallel to opposite sides of said bottom outwardly. thereof and defining at each side of said bottom a series of panels for forming tubular side walls at opposite sides of the box, each said series including an outer side panel, a top panel, an inner side panel, and a bottom panel connected to each other in that order, upper and lower locking tabs, extending from said top and bottom wall panels, respectively, at both ends thereof along the ends of said inner side panel and being separated from said inner side, panel by slits in the blank defining the opposite ends of said inner side panels, said upper and lower locking tabs being separated from each other by slits intersecting. said first mentioned slits, locking flaps extending from said' outer side panels along substantially the full width thereof, a series of panels extending from the other two sides of said bottom for providing tubular end walls on the box, each of said last mentioned series including outer end panels, top end panels, inner end panels of lesser width than said outer end panels, and bottom end panels adapted for tucking beneath said lower locking tabs to retain said end walls in tubular form on the erected box.

4. -A unitaryblank for forming a doublewall box comprising asheetof material. havingscore lines therein defining a generally rectangular bottom, a plurality of score linesextending parallel to opposite sides of said bottom outwardly thereof and defining at each side of said bottom a series. of panels for forming tubular side walls at opposite sides of thebox, each said series including an outer side panel, a top panel, an inner side panel, and a bottom panel connected to each other in that order, strips extending from said top side panels along opposite ends of said inner side panels and bottom side panels and separated therefrom by slits in said blank, each said strip providing an upper locking tab, a connecting strip, and a lower locking tab adapted for adherence to said bottom at the corners thereof, locking flaps extending from opposite ends of said top side panels and the adjacent edges of said top locking tabs and adapted for folding into a vertical position extending between said upper and lower locking tabsin the assembled box, a series of panels extending from the other two sides of said bottom for providing tubular end walls on the box, each of said last mentioned series including outer end panels, top end panels, inner end panels of lesser width than said outer end panels, and bottom end panels adapted for tucking beneath said lower locking tabs to retain said end walls in tubular form on the erected box.

References Cited in the file of this patent UNITED STATES PATENTS 2,457,812 Epps Jan. 4, 1949 2,514,384 Frankenstein July 11, 1950 2,628,763 Frankenstein Feb. 17, 1953 2,687,839 Gray Aug. 31, 1954 2,755,982 Vander Lugt July 24, 1956 FOREIGN PATENTS 7 739,590 France Oct. 8, 1931 

